Effect on global and static variables in CreateVBHeaderCopy not understood

[Simi699]

Hai thetrik,

To test multithreading using modMultThreading2.bas I made a
standard exe project containing form1,module Module1 with global variable gi and added your
modMultiThreading2.bas.

Form1 code

Private Sub Command1_Click()
gi = 12
vbCreateThread 0, 0, AddressOf abc, 0, 0, 0
End Sub

Private Sub Command2_Click()
MsgBox "in th abc gi=  " & gi
End Sub

Private Sub Form_Load()
modMultiThreading.Initialize
End Sub

Private Sub Form_Unload(Cancel As Integer)
modMultiThreading.Uninitialize
End Sub


module1 code

Public gi As Long

Public Function abc( _
                 ByVal tThreadData As Long) As Long
         MsgBox "in th abc gi=  " & gi
         gi = 70
End Function

The following code is commented from CreateVBHeaderCopy function of modMultThreading2.bas and placed in CreateVBHeaderCopywithoutglobalChange() in order to check effect on global variable.CreateVBHeaderCopywithoutglobalChange is called instead of CreateVBHeaderCopy from ThreadProc in modMultiThreading2,bas.But the gi global variable behaves the same independent of the below code.Please explain with an example how the below code effects global and static variables as I am unable to understand its use in an example practically.

' // In order to keep global variables
' // Change the [vbheaderglobalvarsexperiment.zip](https://github.com/thetrik/VbTrickThreading/files/14648354/vbheaderglobalvarsexperiment.zip), VbPublicObjectDescriptor.lpStaticBytes
pProjInfo = pHeader + &H6A

CopyMemory ByVal pProjInfo, ByVal pOldProjInfo, &H23C

' // Update on VBHeader
GetMem4 pProjInfo, ByVal pHeader + &H30

' // Create copy of Object table
pObjTable = pProjInfo + &H23C

CopyMemory ByVal pObjTable, ByVal pOldObjTable, &H54

' // Update
GetMem4 pObjTable, ByVal pProjInfo + &H4

' // Allocate descriptors
pDescriptors = pObjTable + &H54

CopyMemory ByVal pDescriptors, ByVal pOldDesc, lModulesCount * &H30

' // Update
GetMem4 pDescriptors, ByVal pObjTable + &H30

' // Allocate variables block
pVarBlock = pDescriptors + lModulesCount * &H30

For lIndex = 0 To lModulesCount - 1

    ' // Zero number of public and local variables
    GetMem4 pVarBlock, ByVal pDescriptors + lIndex * &H30 + &H8
    GetMem4 0&, ByVal pDescriptors + lIndex * &H30 + &HC

Next

Project attached
vbheaderglobalvarsexperiment.zip

Simi